Polarization used at the time would cause a very dramatic effect if the viewer were to tilt their head. In the past, some theaters that used passive 3D could suffer from even worse crosstalk than active ones. As the shutter hides the left eye, some TVs might take long enough to display the next image that a faint trail of the previous one remains and leaves an undesirable doubling effect. This is an effect of the TV's response time. For example, on an active 3D TV, if the glasses are not perfectly in sync with the television, one eye can start to see part of the picture meant for the other eye. First, some televisions don't do a good job of displaying the correct picture to each eye. There are two reasons why you may experience crosstalk. This is, of course, the extreme case, where the complete picture has crosstalk (with normal usage, only small parts of a screen will show that defect). The best way to experience what crosstalk looks like is to remove 3D glasses in a theater. It will make a section of the picture blurry - usually the edges of an object.